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Discussion Starter · #21 · (Edited)
NEW ENGINE

Finally, I'm pretty much all caught up. I'm glad I started this journal, it's crazy to see (almost)all that's been done in one place. When I think about it, 3 years ago I couldn't tell the difference between endlinks and axles, and now I'm about to swap a whole engine. This project has kept me motivated to go forward in life and accomplish more so that I can keep fuelling this passion. Some would see it as a huge waste of time and money, I seriously don't know where I'd be today if I hadn't done this. NO RAGRETS

But I'm having a well known issue with my car: it started having a drinking problem about a year ago. Quarts after quarts of oil couldn't quench its thirst. I can't do 2000km without having the low oil level indicator lighting up. After inspection, we found leaks in many places. The main leak comes from the front crankshaft seal, but both valve covers are leaking as well. There's so much oil it's hard to tell but I suspect the timing chain cover and/or oil pan seal to be leaking too. To add to this, I have some idler pulleys that are dying, and my (30 000km old) V-belt started squealing not too long ago. The squealing stopped when I switched back to my old (130 000km old) belt so I don't know if the new one was so cheap it stretched or if the tensionner is going out.

Some people woud be pissed that this happens to a relatively low mileage car (165 000km), my old Mazda died of rust cancer at 280 000km and engine never needed an ounce of oil between changes. But I'm quite happy, this gives me a legit excuse to go for another engine. In the search of more power, time, money and experience are all limitations. With my set of skills and financial ressources, I decided to go for the simplest upgrade possible.

Here's what I got
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It's an FB25b longblock from a 53 000km 2015 Forester. All and all I paid 1500$ CAD for it and it has a 1 year warranty. This engine would allow me to gain a little more power, actual real power, to the car. Although some work still needs to be done for it to work, I will be able to keep my ECU, wiring harness and sensors without having to mess with the CANBUS system.

Obviously, I never touched an engine before. But I'm confident that with good advice and enough reading/preparation, it'll work. My previous projects started from simple to complex in order to help me ramp up my skills to the level where this is the natural next step.
 

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Discussion Starter · #22 ·
Here's my dilemma with my engine swap project: do I take the easy route or do I go all the way right now? There is one thing that I've been really dreaming of since I got this car and it is to make a completely custom supercharger setup to boost the car. Some people would jump to the power adder as soon as possible but I did the opposite: Learned my way through simple mods, made the car ''power ready'' through upgrades in the braking system, transmission, intake/exhaust, slight weight reduction and handling.

Now I'm getting a bigger engine because maybe, I don't know, maybe the new power level will be enough for me and I won't go through boosting it. Having a bigger displacement engine will allow me to reach my power goals with less boost and also the fact that it has lower mileage will help me mitigate the impact on reliability. Ideally I would target something between 5-8lbs of boost because that's what the commercially available kits advertise as ''safe on stock engines''.

So what would be the best thing for me to do? I know that the FB engines are somewhat fragile and there are so many paths I could take from here. The easiest would be to just swap the engine as is, maybe eventually boost it when I'm more comfortable with tuning (at least a year from now) and make it endure the stress for as long as it can. During that time, I would be able to find another block that I could focus on learning engine building with so that when the FB25 dies, I am ready to put something that is more power capable inside.

I could also do a complete rebuild with OEM components but I'm not sure it's worth it with a 53 000km engine.

OR, I could do a rebuild and replace some of the components with aftermarket parts to make the engine solid enough to handle power adders later on. My old engine still runs, I have some funds and the whole winter to get this done, so it's a good timing too. The only problem with this option is that I would require help and advice to chose which components to invest in and figure how all this custom work would fit together.

What's on the table:
Engine reseal with turbo gaskets
Changing the piston rings
Changing the rod/crank bearings
Head stud upgrades
Piston/rod/rod bolts upgrades (FA24F pistons are the same diameter so maybe there's something to do here)
Head work (porting)
Valve springs/retainers/rockers
Swap with FA20 internals? Not sure how much work is needed to fit the crank.
Frankenstein engine with FB25 block and FA20 heads? I don't think I'm ready to tune such a beast.
 

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Discussion Starter · #23 ·
After writing all of this, it seems more and more clear that I should go with the first option. I've done all of this with patience and prudence and it seems like I would be rushing it to dive into engine building without prior swapping experience. When I do medical research, I always try to reduce the number of unknowns to it's minimum because it makes the issues easier to resolve. Unless someone points to me a clear path to follow, I think I should try to keep it ''simple''.
 

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I’m really enjoying your thread. What’s not to like about car porn? I saw in the second picture in post #13 that you have the most important tool for any modifications. If it was me, I would do a tear down of your new engine and fix or replace any items that show wear or damage. Having just gone through this with my Cherokee engine, it’s alot easier to do the work with the engine on a stand. and you’d know what you’ve got from the start. Thanks for the posts.

Doug
 

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2021 Crosstrek Outdoor - "Trekov"
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Wowzers! That has been a serious learning curve for you. It would be for anyone who doesn't make their living by wrenching on cars.

I admire both your energy and your "damn the torpedoes ... full speed ahead! " mindset. :cool:
 

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Discussion Starter · #29 ·
Had some friends help me put the FB25b on a stand. First I want to clean it up and try to make it look new. Even though it gets dirty quickly, I find it more motivating to install parts that look clean/new.
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I'm trying to plan all the work I have to do on it and maybe make some kind of roadmap/checklist for when I'm ready to do the swap so I don't end up making stupid mistakes.

Here's what's broken so far (original car got hit on passenger corner):
Timing chain cover is cracked
Crank pulley is cracked
Intake cam position sensor connector broken
Idler pulley bearing sounds finished
A couple of wires on the harness are ripped

It ain't really a problem, I don't need any of those parts since I'll be swapping them with the FB20b components. I feel lucky because those broken parts that I don't need helped me get a lower price/mileage on the engine.

The only thing that really worries me is that I don't know if the impact that cracked the crank pulley bent the crankshaft. The engine turns and has a 1 year warranty on parts and labor so it's not too bad but I'm trying to have as little downtime as possible on the car. I think I won't know for sure unless I open the block or make it run.

First I'll do a leak down test, then when I remove the timing chain cover, I'll try to figure out if anything else got damaged because of the impact. After that, I hope I'll be able to decide if I need a rebuild or not.
 

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Discussion Starter · #30 ·
Had some fun learning how to polish aluminium. I tried my luck on the fuel rail covers of my future engine.
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It took me about 4hours of trying different approaches on the inside and doing the first one.

After seeing the results, it kind of makes me want to do other parts as well, like the TGV, throttle body, coolant crossover and brackets. We'll see how my motivation goes.

In the great scheme of things, I am hoping that getting comfortable working the aluminium for aesthetics will prepare me for when I want to take on a port and polish project.
 

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Discussion Starter · #31 ·
Today I started stripping the engine. Removed the harness, TGVs, alternator bracket and coolant crossover pipe.

I was pleasantly surprised by how clean the valves and intake ports are after 53 000km. If the crankshaft is OK, a full rebuild won't be necessary.
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This engine definitely doesn't need an oil catch can ;)
 

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Discussion Starter · #32 ·
My car got hurt during the Christmas holidays. It was a stormy day with very strong winds. I usually try to park in spots where there are no cars next to mine to reduce the risks of accidents, but this time I felt ridiculous. I was parked like 10-20 meters away from the nearest car, super far from the store doors in an empty parking bigger than a baseball field.

After 10 minutes in the store I come out and what do I see? Another dude decided to park like 2 feet away from mine. It was so close I couldn't figure out how he got out of his car. As I approached, wondering how the **** can someone do that when there's litteraly hundreds of free spots that are closer to the doors, I hear the guy from inside his car: Hey sorry! The wind took my door out of my hand and it hit your car... Christmas facepalm

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The guy kept saying he was sorry and it was an accident but couldn't figure out how he could have avoided this... Anyways, I told him I'm just glad he didn't hit and run, it's in the insurance company's hands now.
 

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Discussion Starter · #33 ·
I did a leakdown test on my FB25b
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Spark plug channels were super clean with no oil.
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At 53 000km, spark plugs are at about half their lifespan. All 4 had a gap of 1mm +/- 0,02mm and looked ''good'' (based on my limited experience). I'm not sure if I should keep them or replace. I know they are cheap but I don't like wasting.

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I ordered a cheap tester from Amazon. The reviews got me a little worried about the quality but it turns out people just don't know how to read instructions. 😅 What worried me the most was the reader's precision and placing the pistons at TDC so I did 2 measurements per cylinder and turned the crank a full cycle in between.

Cylinder #Leak down average (%)
17.5
27.5
32.5
412.5

As a reminder, here's the piston disposition:

Radiator (front of the car)
|2 1|
|4 3|
Transmission (rear of the car)

I don't have a specific acceptable range for this vehicle but according to the internet, a cold engine with values under 15-20% is healthy. Readings were pretty consistent and I don't really have outlier values so I assume my piston rings and head gaskets are in good shape. I also tried raising the air pressure to 100 PSI and couldn't hear anything coming out of the oil pan or coolant lines. Most of the air was coming out from the exhaust valves, which I guess would make sense considering they have some carbon buildup.
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I will look at methods for cleaning this side a bit. One thing that surprised me is that when talking about exhaust gas scavenging, we have equal lenght and unequal lenght header designs. Equal lenght is the most efficient design while unequal lenght gives the classic Subaru rumble. When I looked at my exhaust ports, the front one is directly over the valves while the rear one has a much longer, angled channel. Those are definitely not the same lenght. I wonder how/if this lenght difference is accounted for in header designs and if it affects the dynamics of gas scavenging.

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I started loosening the timing chain cover bolts and when I turned the engine upside down, I found a small leak on the cover, vis-à-vis the headgaskets. The leak is very small and looks fresh/clean so I am assuming it was caused either by the impact of the accident or me loosening the upper cover bolts. Hopefully this problem doesn't follow me after the swap.
 
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